This renewal application for an independent scientist award (K02) seeks to support the candidate toward gaining knowledge and acquiring necessary skills for incorporating genetics into his investigations on the developmental pathways of youth drug behaviors, including substance use disorders (SUDs). The intensive period of study afforded by the renewal K02 will involve course work, workshops and consultations with experts in the field of genetics and addictions. Supported by a funded R01, the research development plan will enhance the analysis of current longitudinal data sets and the development of future studies of existing prospective samples. Specific career development goals include: (1) gaining an understanding of the use of state-of-the-art methodologies pertaining to collecting, storing and genotyping genetic material for use in genetic analyses;(2) developing expertise in the use of statistical techniques on longitudinal data involving genetic and environmental variables;(3) gaining expertise in applying gene-environment analyses to existing prospective data sets in order to test and validate gene-environment models that inform our understanding of developmental pathways of adolescent drug use behaviors;and (4) continuing a commitment to teaching service and responsible conduct of science. The applicant's enhanced research skills in genetics will be applied to existing prospective longitudinal samples in order to advance knowledge on the causes and consequences of youth drug use behaviors. These samples represent three groups: high-risk (n=274), treatment (n=393), and matched control (n=190). All samples have already been followed at multiple points (4 waves of assessment) up to their current young adult status (average age is 22.1 years), and the supporting R01 will include two more waves of assessment and the collection of DNA. Study hypotheses will focus on genetic influences, and the interplay of genetic and nongenetic factors on the course and pattern of developmental pathways of youth drug use behaviors. PUBLIC HEALTH RELEVANCE: By further clarifying the nature of developmental pathways of youth drug abuse, prevention and treatment efforts can be better informed.